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17
AK - 53
CHASSIS
DTVOUTN
117
DTV output negative
VCC_SUP
118
supply of supply circuit (5V)
fuse
119
fused lead
CVBSOUTIF
120
CVBS output of IF circuit
GND_SUP
121
ground of supply circuit
VCC1_VSW
122
supply of video switch (5V)
CVBS0
123
CVBS0 input (to be used for CVBS from IF part)
TESTPIN1
124
test pin 1 (connect to ground)
VCC2_VSW
125
supply of video switch (5V)
CVBS1
126
CVBS1 input
R5
127
right input audio 5
L5
128
left input audio 5
Important pins need to be checked in case of troubleshooting
Signal Measure
Value
CVBS/RGB Input voltage
Input pins
1Vpk-pk
CVBS Output voltage
Output pins
2 Vpk-pk
Maximum input audio voltage
Input pins
2 Vrms
Maximum output audio voltage
Output pins
2 Vrms
12.3. CS51033 (IC104)
12.3.1. General Description
The CS51033 is a switching controller for use in dc–dc converters. It can be used in the buck topology with a minimum
number of external components. The CS51033 consists of a 1.0 A power driver for controlling the gate of a discrete P–
channel transistor, fixed frequency oscillator, short circuit protection timer, programmable Soft Start, precision reference,
fast output voltage monitoring comparator, and output stage driver logic with latch.
The CS51033 is a switching controller for use in dc–dc converters. It can be used in the buck topology with a minimum
number of external components. The CS51033 consists of a 1.0 A power driver for controlling the gate of a discrete P–
channel transistor, fixed frequency oscillator, short circuit protection timer, programmable Soft Start, precision reference,
fast output voltage monitoring comparator, and output stage driver logic with latch.
The high frequency oscillator allows the use of small inductors and output capacitors, minimizing PC board area and
systems cost. The programmable Soft Start reduces current surges at start up. The short circuit protection timer
significantly reduces the PFET duty cycle to approximately 1/30 of its normal cycle during short circuit conditions.
The CS51033 is available in an 8–Lead SO package.
systems cost. The programmable Soft Start reduces current surges at start up. The short circuit protection timer
significantly reduces the PFET duty cycle to approximately 1/30 of its normal cycle during short circuit conditions.
The CS51033 is available in an 8–Lead SO package.
12.3.2. Features
• 1.0 A Totem Pole Output Driver
• High Speed Oscillator (700 kHz max)
• No Stability Compensation Required
• Lossless Short Circuit Protection
• 2.0% Precision Reference
• Programmable Soft Start
• Wide Ambient Temperature Range:
• High Speed Oscillator (700 kHz max)
• No Stability Compensation Required
• Lossless Short Circuit Protection
• 2.0% Precision Reference
• Programmable Soft Start
• Wide Ambient Temperature Range:
Industrial Grade: –40°C to 85°C
Commercial Grade: 0°C to 70°C
Commercial Grade: 0°C to 70°C
12.3.3. Pin Description
PIN NUMBER
PIN SYMBOL
FUNCTION
1 V
GATE
Driver pin to gate of external PFET.
2 P
GND
Output power stage ground connection.
3 C
OSC
Oscillator frequency programming capacitor.
4
GND
Logic ground.
5 V
FB
Feedback voltage input.
6 V
CC
Logic supply voltage.
7
CS
Soft Start and fault timing capacitor.
8 V
C
Driver supply voltage.
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